tests Flashcards
(19 cards)
what is the test for ammonia (NH3)
turns damp red litmus paper blue
OR
turns damp universal indicator paper blue/ purple
what is the test for ammonium
add OH- (alkaline)
this removes 1 H+
this now ammonia (NH3)
turns damp red litmus blue
what colour flame does Li+ (lithium) make
red
what colour flame does K+ (potassium) make
lilac
what colour flame does Na+ (sodium) make (close to colour of salt)
yellow
what colour flame does Cu2+ (copper) make (statue of liberty)
green
what colour flame does Ca2+ (calcium) make
orange
what is a precipitate
an insoluble solid formed from mixing 2 soloutions
what is ion called when it’s not involved in a reaction
a spectator ion
what precipitate does Fe2+ form with NaOH
green
what precipitate does Fe3+ form with NaOH
basically rust
brown (basically rust)
what precipitate does Cu2+ form with NaOH
think crystals
Blue (copper sulfate crystals)
what precipitate do Ca2+ , Mg2+, Al3+ form with NaOH
all form white precipitate
Al3+ (soluble in excess and others are insoluble)
How to test for carbonates (end in Co3,2-)
add any acid
gas produced (turns limewater cloudy)
fizzes is how you see gas produced
how to test for sulfates (end in SO4,2-)
add HCL
add barium chloride
white precipitate formed
BaCl2+ (aq) + So4,2- (aq) = BaSO4 (s)
how to test for halides (end in Cl-, Br-, I-)
add nitric acid
add silver nitrate
Cl- = white precipitate
Br- = cream precipitate
I- = yellow precipitate
AS YOU GO DOWN GROUP 7 GETS DARKER
how to test for magnesium
burns in oxygen producing bright white light
how to test for sulfir
burns in oxygen with blue flame
how to carry out a flame test
clean nichrome wire
dip in sample
hold in roaring blue flame
